Molding apparatus



Dec. 2, 1930. F. J. LEUTHNER 1,783,805

MOLDING APPARATUS Filed Aug. '2, 1929 2 Sheets-Sheet l A INVENTOR f @wwwDec.- 2,1930.

F. J. LEUTHNER MLDING APPARATUS .Filed Aug. 2, 1929 2 Sheets-Sheet 2 es;A

i ingmeans is claimedin Vmy Vcopending appli-l Patented ec. 2,

Unirse srAfljES Yrmiixx I. IJEUTHNERQOF sHARPsvILLE, PENSYLVANIA- Y 'dMQL'DING APPRATUs `ApplicatrinV filed August 2, 1929.l Serial No.382,941.

`This V,invention relates to molding appa-V ratus, andmore particularlyto an improved core and extractor constructionfor use With molds forhollovvcastings.V The invention still moreparticularly relates to animprovedeollapsible core and extractor particularly adapted for ingotmold casting` The extractcation, Serial No. 482,17 0, filedSept.j16,1930 which applicationis a division of'this application.

1As is well knovvnin the art, an ingot mold is cast'in a mold having anouter flask or chill and a central core `member for Vproviding the ingotcavity.` It has longbeen the practiceto cast ingot'molds Whoser Wallsare *substantial-V ly: straight ,from end to end by the use of vacollapsible core. i The known typev o f collaps-` ible core and thestraight-sidedingo-t moldsV which could be Vcast byfthe use thereof areshown, for example,in United States Patents Leuthner," and No.1,018,669, issued to lsaid 1 Nos. 868,607 and 1,018,668,issuedtoFrankfX.

Le'uthner and Frank -Ticknenl ASuch collaps' ible cores comprise acentral body or core barv surrounded by plates Whichv are spacediapartat their edgesY and supported on the central core bar, the bar beingtapered so that upon substantially axial movement inl the direction ofits larger end, the plates areallovved tot collapse inwardly, therebyfacilitatingjthe removal of the core from thecasting.

In the casting of ingot molds lWhoseWalls are :substantially straightfrom end to end, it

has been customary to use such collapsible corebars Which have :theirupper portions extending a considerable distance above the side platesand above the topsyof the castings. As

vWill be seen from the patentsabovereferred to, collapsible core bars ofthis nature are adapted only for vuse in casting such straight sidedmolds. 1 The sizeof the upper portions thereof projecting-abovethetopof'the castingpreclu'des their usewith a casting-Whose shape at thetop isother thanjsubstantially straight. Y

Y Modern practice ifs tending tovvard the useV ofingot moldsWhosevvalls'neck in at the top,

considering the molds inthe position they vassume While they are beingcast. VSuch' a mold Y uniform.

is inverted When-used vfor pouringingotsiso i that the-necked-in portionserves as the` bot-4 tom of the mold cavity and assists in shaping theingot ,andVV in: reducing the amount of" poured metal 1Which comes incontact with the bottom of the mold. Amold 'of thistype cannot be castabout a collapsiblel core of"V the type` above mentionedbecause ofthevfact that PATENT OFFICE the 'size of'such core;precludesV theformation of the necked-in top as the metal is poured. .It hastherefore, becomethe `common practice 1n casting necked-in molds to usesolidV cores Which do not have Va large upper `extremity Vextendingabovethe top of-the casting.

The problems involvedv in theremoval of a solid `core from a castingotmold havejbeen well known for years. .It is necessary tolay .theflask, casting and core onftheir'sides'and to ram ,the coreand flaskapart. This operation is very detrimentalv to the flasks and cores vvand,also` time Wasting and therefore expensive. In fact, no fullysatisfactory corehasheretoforebeen provided .for the Y Y casting of.necked-in molds.

A Furthermore, hen necked-inr-molds are cast usingsolid cores, the,gases which form,

during 'the casting 'operation 'are confinedV VWithin the molds,vproducing bubbles and holeswhichare, to say the least,detrimental, andwhich in. manyinstances entirely spoil the castmolds. This is`particularly true lof bubblesk andholes formed inthe ingot cavity,

which 4should necked-in-ingot molds., llalsof'provide an improved vcore,extractiii'g meansv adaptedforf use With an improved collapsible coreWhere-1.

by. togreatly facilitate, quicken and cheapen'lV Y the lmval 0f Coresfrom. cast necked-in ingotfmoldsf Y a l 'I provideA molding apparatusComprising a collapsiblev core havinginnerrand Voutercorel l members,the innerscore member having 'a pin of relatively `'small diameter ascompared With-,the size of such inner core member connected with thetopYthereof and Vve'xte'nding vertically therefrom. I further providemolding` apparatus comprising an extractor having means for engaging afiask and means for engaging a core for removal of the core from theflask, and a centering sleeve sldably connected with the extractor. Istill further provide molding apparatus comprising a core and anupwardly extending member connected with the top thereof, such memberhaving means for leading off gases formed about the core.

Other objects and advantages ofv the invention will become apparent asthe following description ofva present preferred embodiment thereofproceeds.

In the accompanying drawings I have shown a present preferred embodimentof the invention wherein Figure 1 is a central vertical cross-sectionthrough molding apparatus having an ingot mold cast therein;

Figures 2 and 3 are side views to enlarged scale of a centering sleeve;

Figure 4 is a top view of the centering sleeve;

Figure 5 is a bottom view of the centering sleeve;

Figure 6 is a top View of a retaining block for the centering sleeve;

Figure 7 is an end view of the retaining block;

Figure 8 is a top view of the extractor pin; and

Figure 9 is a pin.

Referring more particularly to the drawings, reference numeral 2designates a mold base upon which is set a tapered core bar 3 whichforms the inner member of a collapsible core. Cooperating with the bar 8are side plates 4 supported in the position shown in Figure 1 by the bar3 and held inwardly by bolts Upon downward movement of the bar 3 theside plates 4 of the core collapse inwardly, whereby to facilitateremoval of the core from the casting. So much of the construction as isdescribed above is well known in the art.

side rview of the extractor rllhe core bar 3 has a top opening 3a fromthe bottom of which to the interior of the core bar leads a duct 3b.Fitting into the opening 3a is a pin 6 which is preferably of steel. Thepin 6 is positively connected with the core bar 3 by a key 6a whichpasses through the core bar and the pin to maintain the latter in place.Instead of being keyed to the core bar, however, the pin 6 may beconnected therewith by being cast integral with the core bar, by drivenfit or by any other suitable means.

Extending longitudinally through the pin 6 is a duct 6b. This ductcommunicates with the duct 3b at its bottom and alsohas lateral branches6c leading out through the pin 6 above the point of connection of thepin with the core bar. The ducts are for the purpose of leading ofi'gases formed about the core during the casting operation. Unless suchgases are led off, they form imperfections in the casting as abovementione l. The ducts provide a means not provided by a. solid core forleading off the gases. I/Vhen a solid core is used, whatever gases donot find their way out by leakage remain within the casting and are anendless source oftrouble.

The pin 6 is'of small diameter as compared with the size of the innercore member and is of substantially the same diameter as the hole to beprovided in the top of the cast ingot mold (which will be in the bottomof the mold when used for casting ingots). A sand mold wall 7 is formedabout the core by the use of a' suitable pattern, as well known in theart. A Hask 8 also re-'ts upon the base 2 and is centered with respectto the core. A sand cheek 9 is formed within the flask 8 also with theuse of a pattern. The bottom of the core bar 3 is provided with alateral extension 10 which joins the sand cheek and upon which the sandcore wall 7 rests. The extension 10y therefore serves as the bottom ofthe mold cavity for casting the ingot mold. rIhe sand walls 7 and 9serve respectively the inner and outer mold surfaces, the metal 11 beingpoured in to form an ingot mold having a necked-in upper extremity 12.As shown in Figure 1, the metal at the top of the casting substantiallyabuts the pin 6 so that the hole through the top of the casting is onlyslightly greater in dialneter than the diameter of the pin.

n In order to collapse the core it is necessary to exert a downwardpressure on the top of the pin 6 whereby the core bar 3 moves downwardlyand the side plates l collapse inwardly, the entire core then fallingout. I provide novel extracting means adapted for use with the improvedcore to effect extraction thereof. The extracting means comprises a ring13 adapted to be connected with a crane hook, such ring having connectedtherewith a pair of oppositely disposed chains 14. Pivoted to theextremity of each chain 1&1 is a lever 15. Pivoted to the inner ends ofthe respective levers 15, as at 16,16, is an extractor pin 17 (seeFigures 8 and 9. Iivoted intermediate the ends of the respective levers15 are chains 18 to the end of each of which is connected a hook 19adapted to underlie and engage with a flange 2O on the flask 8.

Slidably carried over the extractor pin 17 is a centering sleeve 211(see Figures 2, Z3, l and 5) which sleeve has four upward extensions 22eachhaving a strengthening rib 23 and each being lprovided at its upperextremity with a hole 211. The extensions 22 merge into the sleeve 21,which has a substantially cylindrical inner surface 26 whose diameter isslightly greater than' the diameter of theshank 27 of the extractor pin17. The

i as shownV in Figure 1, Va retaining block 28 V`isv not needed for theextracting operation.

having holes 29 being inserted between thev extensions 22 and pinsfitted through the holes 24: and 29 to prevent the sleeve from becomingdisengaged with the pin. The lower partY of the sleeve has strengtheningflanges 30, as shown 1n Figures 2 and 3.

The internal diameter of the centering sleeve is somewhat greater thanthe external Vdiameter of the steel pin 6 in the core andis adapted toembracethe upper part of the pin 6 to center the extractor thereto. Y

The flask is picked-up through the agency pin 17l with respect of theextractor, and the core is extracted at the same time. Acrane hook islowered over the assembled flask and core having the cast? lng formedtherein'.V The vhooks 19 arsengaged with the flange 2O of the flask, thering 13 is engaged with the crane hook and the sleeve 21 is placed overthe upper extremity of the'pin 6. "The crane hook is then raisedupwardly, bodily lifting the flask, and by so doing a downward pressurep isl exerted through the levers 15 and the extractor pin 17 against thesteel pin 6 in` the core,where by the core is collapsed and lthe flaskis raised upwardly 4by the crane, the core drops out. v The extractingoperation, when an ime` proved collapsible core and an improvedextractor, such as herein disclosed, are used, isV

greatly simplified over the previous method wherein the flask, core andcastingA were laid on their sides and the core and ilaskrammed apartwith the attendant damage, delay and expense, as above mentioned.v Y Thepin vG serves not onlyto define the opening inthe casting, but also toimpart the force exerted by the extractor vpin 17 to the core bar,.whereby the collapsible core maybe Vextracted from withinA the casting. Thecentering sleeve may be easily lowered over 'the upper extremity ofthepin 6 and serves tol positively center and position the extractor pinwith respect to the core pin so that the downward force exerted by thevextractor upon raising the crane hook is 'axial not only through the`extractor pin,vbut 'also through the steelccre pin.` This preventsdamage to the extractor or VtheV core' and efv fectively provides forready extraction. 1

Vhen the construction above described is used, so little pressureneedfbe'broughtto bearA uponthe pin 6inl order to extract the core thatthe full cross section of ythe'pin and consequently the ducts V6b and6c, above described, may be. formed in thev pinV withoutA While no?.'claim' fmade toria fcollrapsible". corefper'fs'e,ortoi1an extractorerase, bothI of .these .devicesibeing admittnedlVp !;old;I; am',so'lfar: as I? amil aware, the "rst ftofn'ialtke .available foruseiincasting inecked-in'in'got molds followingclaims;

f Ic'laim:` g ,a 1 y l. V'Molding' apparatus, comprising a collapsiblecorehaving inner,` andqouter .core

variouslvf embodied lwithin the. scopeof the members, theinnercore'member havingA a hole `in its top receiving anVvupstandingpin,v

andcommunicatingvducts Vin the top of the f inner `core;memberpbelow`thehole and .in the. ,p1n.i;f. f

2. Molding apparatus, comprising acoli'apsible core havlnginnerand outer'core members, the: inne'r core `member `having-a pin vjoinedintegrallywith its topl andcextending therefrom and asand moldwallcoverf ing .the'sides and? the top of the outer core l'nember to thesides of the pin. v

SLLApparatus for' forming sand molds, comprising a collapsible corehaving inner ,and outer core members, the inner core mem- Vber having apin of relatively small diameter Aas compared with the size of suchinner core member connected with the ltop thereofV and *extendingvertically therefrom, and l molded sand covering the sides andtop ofVthe outer coreV member to the side walls of said pin. l

LYAvcollapsible core against which sand is yadapted .to be molded,comprising inner Vand outer core members, the inner coremember having'Van upward extension of Areduced ina e' size extending above-the outercoremember,

and molded sand lyinggenerally upon its upper surface and against theextension ofi `the inner core member.

Molding apparatus, comprising acollapsible core having inner and outercore members, the 4inner coreV member having a socket for receiving anupstandingpin, the outer core'member havingits Vupper portion Y'1n-embers, the inner core member having Aa socket for receiving anupstanding pin,the outer core member having its lupper portion turnedinwardly above the socket in the inturned inwardly above the Asocket inthe inl-ZYO ner core member, and a pin in the socket of the inner coremember and extending above the outer core member, the inner core memnber and pin having communicating duets.

7. Molding apparatus, comprising a eollapsible core having inner andouter Core members, the inner core member having a socket for receivingan upstanding pin,the outer core member having its upper portion turnedinwardly above the socket in the inner eoremember, and a pin in thesocket of the inner core member and extending above the outer coremember, the inner core member having a duet leading from its interiorand terminating in the socket, and the pin having a duet communicatingwith the duet in the inner Core member.

8. Molding apparatus for casting ingot molds, comprising a flask, acollapsible core therein having inner and outer members, Jthe upper endof the outer member being below the upper edge of the flask, aV pinextending upwardly from the inner member, and a sand wall on the face ofthe outer member on the sides and top to the side of the pin, therebeing space for the reception of molten metal above the sand -wall andbelow the upper edge of the iiask to form necked in Walls of the molds.

In testimony whereof I have hereunto set my hand.

FRANK J. LEUTHNER.

